NAME

SYNOPSIS

DESCRIPTION

[CX] The functionality described on this reference page is aligned with the ISO C standard. Any conflict between the
requirements described here and the ISO C standard is unintentional. This volume of IEEE Std 1003.1-2001 defers to
the ISO C standard.

The tmpfile() function shall create a temporary file and open a corresponding stream. The file shall be automatically
deleted when all references to the file are closed. The file is opened as in fopen()
for update (w+).

[CX] In
some implementations, a permanent file may be left behind if the process calling tmpfile() is killed while it is processing
a call to tmpfile().

An error message may be written to standard error if the stream cannot be opened.

RETURN VALUE

Upon successful completion, tmpfile() shall return a pointer to the stream of the file that is created. Otherwise, it
shall return a null pointer [CX] and set errno to indicate the error.

EXAMPLES

Creating a Temporary File

The following example creates a temporary file for update, and returns a pointer to a stream for the created file in the
fp variable.

#include <stdio.h>
...
FILE *fp;
fp = tmpfile ();

APPLICATION USAGE

It should be possible to open at least {TMP_MAX} temporary files during the lifetime of the program (this limit may be shared
with tmpnam()) and there should be no limit on the number simultaneously open other
than this limit and any limit on the number of open files ( {FOPEN_MAX}).